The Sixth Doctor was a controversial take for fans of Doctor Who, especially after a short-lived, but memorable performance by Peter Davison just prior. This new Doctor regenerated during a time of great stress, where he came closer to losing his life than perhaps any other version of himself. As such, he awoke feral, unfocused, and dangerous.
After settling, the Sixth Doctor's personality traits came out in full force. He was short-tempered, arrogant and prone to complaining, but he was also moral, just and ferociously defensive of the innocent. Here's 10 of the most memorable quotes the Sixth Doctor ever uttered, and how they'd help his character evolve.
The Twin Dilemma
"I would suggest, Peri, that you wait a little before criticizing my new persona. You may well find it isn't quite as disagreeable as you think."
The Doctor's regenerations always gave his companions reason for pause, but the Sixth Doctor was altogether different. His regeneration was particularly chaotic and traumatic, sending him into a flying rage that nearly ended with him killing Peri. After the incident had passed and the Doctor gained a semblance of control, he tried to convince her that this new regeneration might not be so bad, after all.
Attack Of The Cybermen
"I don't think I've ever misjudged anybody quite as badly as I did Lytton."
Attack Of The Cybermen saw the return of Lytton, a villain from the Fifth Doctor serial "Resurrection Of The Daleks" who broke Davros out of prison before earning the ire of his Dalek masters. When the Supreme Dalek attempted to assassinate him, he fled with his two lieutenants and showed up later trying to find a hidden Cyberman base in London. In truth, Lytton was a double agent with benevolent intentions who betrayed the Cybermen, and lost his life in the process. The Doctor was deeply saddened not only by the loss, but his harsh critique of Lytton as a man.
Vengeance On Varos
"It's all right for you, Peri. You've only got one life. You'll age here in the TARDIS and then die. But me, I shall go on regenerating until all my lives are spent."
The Doctor would do a little bit of foreshadowing here when he referenced his age in comparison to a human lifespan, and the method by which Time Lords regenerate. Here, he makes it clear that the Doctor's regenerations are finite, a plot device which would continue right up to Matt Smith's portrayal of the character - the first of many unfortunate retcons.
Mark Of The Rani
"Well, since we're insulting each other, I can't say I care much for your taste in clothes. Doesn't do a thing for you."
The Master's only equal in the small pool of renegade Time Lords is the Rani, a brilliant but amoral scientist with little regard for the lives she destroys. Ever-an-enemy of the Doctor, the Rani would frequently engage in banter with her nemesis, even if it got juvenile. The Sixth Doctor jabbed her with this quote; ironic given his own taste for flamboyant, eccentric clothing. Self-awareness level? Zero.
The Two Doctors
"That is the smell of death, Peri. Ancient must, heavy in the air. Fruit-soft flesh peeling from white bones. The unholy, unburiable smell of Armageddon. There's nothing quite so evocative as one's sense of smell, is there?"
The Sixth Doctor might have kept the same comical edge as some of his predecessors, but he was also prone to diving into dark subjects with nothing in the way of a filter. Here, he illustrates the concept of death, and the odor it produces, which is more than enough to turn anyone off of the conversation.
Timelash
"Should there be another day, I'll explain to you in great detail which of the many time laws I am not allowed to transgress."
While the Doctor did find himself an anomaly in many incidents that took place across the span of time and space, he also knew his limits. Here, the Sixth Doctor talks openly about certain laws of time that even he cannot meddle with. This plot device would turn up in the 2005 continuation of the series, when the Ninth Doctor made several references to the penalties of breaking the rules of time.
Revelation Of The Daleks
"A Knight of the Grand Order Of Oberon! Only I would be stupid enough to attack such a person!"
The Sixth Doctor wasn't afraid to get violent if it meant his life, or the lives of others. He was one of the few Doctors to use a gun, and he wasn't opposed to a bit of fisticuffs, either. When Orcini infiltrated Davros' secret Dalek facility in the bowels of Tranquil Repose, the Doctor tried to ambush him, thinking he was an enemy. He was easily subdued and knocked to the ground, prompting this quote. In reality, he's lucky he didn't lose his life.
The Mysterious Planet
"Planets come and go. Stars perish. Matter disperses, coalesces, forms into other patterns, other worlds. Nothing can be eternal."
For a Time Lord, the concept of eternity should be routine, but the Doctor makes it clear that this is not the case. This quote sums up his views on the universe, and the life within it. It also plays allegorically into the Time Lords, themselves. Even the great Rassilon was not completely immune to the ravages of time. If a race so perfectly in control of time cannot conquer death, then who can?
Terror Of The Vervoids
"This is a situation that requires tact and finesse. Fortunately, I am blessed with both!"
When the Doctor was put on trial for crimes against the universe, the prosecuting Valeyard introduced his conflict with the Vervoids into evidence, in an attempt to charge him with open genocide of an entire species. In the midst of it, the Sixth Doctor wasted no opportunity to display his heightened arrogance; a trait of his regeneration. It's no wonder his companions rolled their eyes so often!
The Ultimate Foe
"In all my travelling throughout the universe, I have battled against evil, against power-mad conspirators. I should have stayed here. The oldest civilization - decadent, degenerate, and rotten to the core! Power-mad conspirators, Daleks, Sontarans, Cybermen - they're still in the nursery compared to us. Ten million years of absolute power. That's what it takes to be really corrupt!"
This quote from the Sixth Doctor is one of the most poignant and powerful, as it plays directly into events yet to come. Audiences would later learn that the Doctor was forced to destroy both the Time Lords and the Daleks during the last Great Time War. His reasoning for destroying his own people would become clear in the 4th season closer "The End Of Time, Part 2," where he revealed the Time Lords' true intention of ascending as higher beings, free from the constraints of time, cause and effect, and creation itself.